Urine does not generally contain glucose except in cases of uncontrolled diabetes and kidney disease, says WebMD. Glucose may also be present in urine during pregnancy, according to the American Pregnancy Association.
When the blood sugar level in the kidneys is too high, glucose leaks from the kidneys into the urine, says WebMD. Renal glycosuria can also cause glucose to appear in the urine. In this condition, even though blood sugar levels may be normal, the kidneys still release glucose into the urine. During pregnancy, it is completely normal for glucose to be present in the urine, says the American Pregnancy Association.